1. Field of the Invention
This invention relates to brush filaments, their method of manufacture and brushes incorporating them.
2. Description of Related Art
Conventional brushes consist of a handle having at one end, a brush head including a plurality of filaments of natural fibre (e.g. animal bristles) or of synthetic material (e.g. nylon) which are of uniform circular cross-section throughout their length. The length, lateral juxtaposition and material of the filaments are selected to provide a desired flexibility for the free ends of the filaments, it being the free ends that in use are, in general, exclusively responsible for the cleaning efficacy of the brush.
Variations in shapes and designs of filaments are known. They include filaments bearing abrasive elements such as scales, serrations, and projections. C.f. U.S. Pat. No. 4,373,541. While these designs can improve the cleaning action of the filament, they can be quite difficult to manufacture. Certain designs may also result in unacceptable flexural stiffness and flexural recoverability of the filament.
The present invention aims to provide a new brush filament, which, in use, can effect improvements in cleaning, whilst maintaining robust flexibility and strength.